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COLAMAN24
10/20/2007, 07:10 PM
This is the first big tank-350 gallon-I've started. I have 2 overflows 6"x12"x6" with 2" bulkheads. My pump can do 7500 gph, question is are my overflows going to keep up? Or do i need to add another one, I have plenty of room.

customcolor
10/20/2007, 08:37 PM
is that 2 bulk heads per overflow or total? and what size are the bulk heads?

COLAMAN24
10/21/2007, 03:21 PM
there is one 2 inch and one 1 1/2 in each bulkhead. the 1 1/2 is for returns but i can run hte returns behind the tank if i need to run both for drains.

kgross
10/21/2007, 03:28 PM
My suggestion to you would be to go with a smaller return pump and use your big pump for a closed loop. It will work much much better, you will have less fighting with microbubbles in the tank, plus you tank will be a lot quiter.

Besides that I'm not sure if a 1 inch and 1 1/2 in each overflow will handle 3500 gph. I setup a tank that has 2 inch in each overflow and that tank has a 3000 gph pump which we can't quite run wide open. I am guessing we are getting around 2000 -2300 gph total, so around 1000 to 1200 gph per overflow. Any more and it gets way to loud.

Kim

Chris Witort
10/22/2007, 11:12 AM
I agree with "kgross" 7500 gph is alot of water and it would be noisy, I doubt 2 2" drains could handle it. The other consideration is that if anything goes wrong it will go wrong fast and will get messy!

rustybucket145
10/22/2007, 11:19 AM
I'd get a 3k ish pump for return and use the 7k for one bad *** closed loop! Get more for your money!!

Ok, Im jealous now.... :D

kgross
10/22/2007, 12:15 PM
I would not even run a 3000 gph pump as a return pump. I would setup my sump system to maximize your skimming. Have your return pump flow just slightly more water than your skimmer processes per hour. Setup your sump so that the water from the overflows goes into a compartment to feed the skimmer, and then the output of the skimmer goes to the next compartment. The only flow flow from the input to the output will be through the skimmer and the slight bit of extra flow that can overflow from the skimmer intake section to the ouput section. Then have the output section go on through the sump. This way you are feeding the most concentrated gunk into the skimmer so it will have a much easier time to remove it. Plus you can make your overflow/sump setup completely quite.

Kim

COLAMAN24
10/22/2007, 01:03 PM
<a href=showthread.php?s=&postid=11025673#post11025673 target=_blank>Originally posted</a> by rustybucket145
I'd get a 3k ish pump for return and use the 7k for one bad *** closed loop! Get more for your money!!

Ok, Im jealous now.... :D

Yeah i've been talking to few other on other sites, Gunna buy a different return pump and use the 7500 for the closed loop.

Just ordered a OM 8-way....

kgross
10/22/2007, 01:09 PM
Which version of the 8 way did you order? I don't think it is really large enough to handle 7500 gph without putting some restriction on the pump unless you have it with multiple outlets open at a time.

Kim